黄山花菇免疫活性多糖FMP1的化学结构研究

文章从黄山花菇子实体中提取分离出均一多糖组分FMP1,采用化学和光谱学等方法对其化学结构进行表征。结果表明,FMP1分子量为9.21×10⁶ Da,由甘露糖、半乳糖和葡萄糖组成,三者摩尔比为1.00∶1.02∶9.33;结构分析显示,(1→4)-β-D-Glcp和(1→4)-α-D-Manp为FMP1的主链,(1→4)-β-D-Glcp的O-2和O-3位以及(1→4)-α-D-Manp的O-3位有分支,(1→3)-β-D-Glcp、(1→6)-β-D-Glcp、T-α-D-Glcp和T-β-D-Galp组成支链;免疫活性实验表明,FMP1能促进巨噬细胞的免疫活性,支链和分子量对FMP1的活性有显著影响。研究结果可为黄山花菇多糖的深入研究及开发利用提供有价值的数据。     

雪莲水溶性多糖XL31的分离纯化及其结构分析

通过采用热水提取乙醇沉淀获得雪莲水溶性粗多糖,经酸性乙醇分级和DEAE-SephdexA-25纯化得多糖XL31.纸层析、醋酸纤维薄膜电泳和Sepharose CL-4B柱层析纯度鉴定表明XL31为均一多糖,分子量约为170kD.其单糖组成为阿拉伯糖(Ara)、鼠李糖(Rha)、木糖(Xyl)、半乳糖(Gal)、葡萄糖(Glc)、半乳糖醛酸(GalA),摩尔比为11:4:1:18:3:9.XL31结构分析采用了高碘酸氧化、Smith降解、甲基化分析及IR、NMR、GC和GC-MS等方法.结果表明:多糖XL31主链由Ara、Gal、GalA构成,其中Ara主要以β-(1→4)或β-(1→5)糖苷键连接,在3-O处有分枝,Gal主要以β-(1→6)及β-(1→4)糖苷键连接,β-(1→6)糖苷键连接在3-O和4-O处有分枝,β-(1→4)糖苷键连接在2-O、3-O和6-O处有分枝;GalA以α-(1→4)糖苷键连接.支链由Xyl、Rha、Glc构成,其中Xyl以1→4或1→5糖苷键连接;Rha以1→2、4糖苷键连接;Glc以1→4糖苷键连接.末端残基为GalA、Gal、Ara、Xyl、Rha、Glc.雪莲多糖XL31是一新结构多糖,为首次从新疆雪莲中分离得到.     

香菇多糖分离纯化及结构表征

采用水体醇沉法得香菇多糖粗品，再通过分级醇沉及Sephadex G-200葡聚糖凝胶进一步分离纯化得到香菇多糖；用硫酸苯酚法测定香菇多糖含量，采用分子排阻色谱法测定香菇多糖分子量，用糖腈乙酸酯柱前衍生化-气相色谱法测定单糖组成，红外光谱(IR)测定多糖结构，结果显示：香菇多糖初次提取纯化的两个组分由β糖苷键岩藻聚糖构成，相对分子量分别为9.5×10⁴和1.7×10⁴.二次提取纯化多糖组分1由岩藻糖、阿拉伯糖、木糖、甘露糖、葡萄糖、半乳糖组成(3.6∶1.3∶1.2∶9.2∶63.3∶21.4),相对分子量4.2×10⁴,以α糖苷键链接；组分2由岩藻糖、阿拉伯糖、木糖、甘露糖、葡萄糖、半乳糖组成(10.7∶1.5∶0.6∶14.2∶25.4∶47.5),相对分子量1.5×10⁴,以β糖苷键链接.香菇多糖结构复杂，其化学结构与生物活性密切相关，通过对香菇多糖的分离纯化和结构表征，可为获取高活性多糖、提升多糖在食品和药品中的应用价值提供科学依据.     

一种从菲律宾蛤仔黏附细菌Halomonas sp.GHF11中提取的多糖絮凝剂的表征其在脱色中的应用

从海洋细菌Halomonas sp. GHF11中纯化出一种新型微生物多糖。本研究首次报道了GHF11胞外多糖的絮凝和脱色活性。实验结果表明,该胞外多糖对高岭土的最大絮凝活性(FR)达到71.3%,去离子水系统中对燃料孔雀石绿的脱色活性达到92.4%。经过分离纯化后,发现该多糖为复杂的杂多糖,单糖组成分析其主要组分为摩尔比为4:1的葡萄糖和甘露糖,甲基化分析发现其糖苷键连接方式有葡萄糖1→2→3→4连接,甘露糖1→2→3→4→6连接。另外,对其絮凝活性进行表征发现,絮凝体系中多糖的用量明显较少,在500μg·L-1时达到最佳絮凝活性,对染料的脱色在1.8 mg·L-1时达到最佳效果。     

坛紫莱多糖的分离纯化和结构分析（Ⅱ）

对广东产坛紫菜沸水提取多糖采用Sevag法脱蛋白,冻干后得粗多糖,得率为8%。在粗多糖溶中加入CTAB以沉淀除去酸性多糖PP1,超滤以纯化中性多糖PP2,PP2经DEAE-纤维素、葡聚糖凝胶G200进一步纯化。经纸层析、凝胶过滤及紫外光谱分析鉴定为纯品。通过红外光谱、气相色谱对PP2进行组成分析,再用化学方法测定其总糖,3,6-内醚-L-半乳糖及硫酸基的含量,分别为86.33%、5.425%和12.2%。最后通过高碘酸氧化,Smith降解等方法测定PP2的化学结构,结果表明,PP2由半乳糖、3,6-内醚-L-半乳糖、甘露糖、葡萄糖、木糖和阿拉伯糖组成,具有α,β型糖苷键,连接方式有（1→3）、（1→4）、（1→2）3种。PP1分子量通过凝胶过滤法初步测得为16.2万左右。     

白沙蒿籽多糖的分离纯化及结构研究

以白沙蒿籽为原料,经水提醇沉,酶法和Seveg法脱蛋白,乙醇分级沉淀,得到两种酸性多糖ASP1和ASP2.将ASP1和ASP2分别完全酸水解、高碘酸氧化、Smith降解后经高效液相色谱分析表明ASP1主要成分是木糖,含有少量葡萄糖和阿拉伯糖,数均分子量2.84×105,ASP2由葡萄糖、半乳糖、阿拉伯糖和甘露糖组成,摩尔比为2.1:1.3:1.0:1.4,数均分子量3.50×104,ASP1中糖苷键以1→3连接为主,ASP2中糖苷键以1→4连接为主,红外光谱及核磁共振光谱表明ASP1,ASP2中均含有糖醛酸为酸性多糖,且均含有α和β两种构型.     

玉米须多糖的提取纯化及结构研究

玉米须经蒸馏水提取、离子交换、分子筛层析等手段得玉米须多糖(SMPS),结构分析研究表明SMPS的分子量约7 000 Da,其单糖组成和比例为鼠李糖∶阿拉伯糖∶木糖∶甘露糖∶半乳糖∶葡萄糖=0. 18∶0. 75∶0. 67∶1. 22∶1. 42∶6. 82; SMPS的重复单元可能是由甘露糖、半乳糖、葡萄糖构成,甘露糖主要以1→6连接存在于主链中,葡萄糖的主要的连接方式为1→3、1→4、1→6连接,木糖在主链及支链中均有存在,半乳糖主要存在于主链的末端.     

茯苓液体培养法中羧甲基茯苓多糖(CMP)的提取、纯化及鉴定

对茯苓菌株HD06-10 进行液体发酵培养,采用醇沉法从其发酵液中提取羧甲基茯苓多糖(CMP).用DEAE-32 纤维素和SephadesG-200 对 CMP 进行柱层析分离提纯,得到主要组分PG.通过紫外光谱和红外光谱对组分PG进行纯度鉴定,结果表明:PG为多糖纯品,未检测出核酸、蛋白质等杂质,仅由羧甲基葡萄糖组成. PG 是β构型的葡聚糖,糖环为吡喃型,糖苷键的连接方式为β (1→3)及β (1→6),分子量大约为4.2×104Da.     

长白山小刺猴头子实体多糖结构的研究

从长白山小刺猴头子实体中提取多糖,其组成是以葡萄糖为主,并夹有少量的半乳糖和甘露糖。经纯化与鉴定得单一葡聚糖,其平均分子量为4万。经结构分析表明该葡聚糖具有多分枝结构。主链由β(1→3)D—葡萄糖残基组成,侧链由β—(1←6)键连结,在分枝或末端有少量β—(1→4)糖甘键。     

坛紫菜多糖的分离纯化和结构分析(Ⅱ)

对广东产坛紫菜沸水提取多糖采用Sevag法脱蛋白 ,冻干后得粗多糖 ,得率为 8%.在粗多糖溶液中加入CTAB以沉淀除去酸性多糖PP1,超滤以纯化中性多糖PP2 ,PP2经DEAE 纤维素、葡聚糖凝胶G2 0 0进一步纯化 .经纸层析、凝胶过滤及紫外光谱分析鉴定为纯品 .通过红外光谱、气相色谱对PP2进行组成分析 ,再用化学方法测定其总糖 ,3,6 内醚 L 半乳糖及硫酸基的含量 ,分别为 86 .33%、5.4 2 5%和 12 .2 %.最后通过高碘酸氧化 ,Smith降解等方法测定PP2的化学结构 ,结果表明 ,PP2由半乳糖、3,6 内醚 L 半乳糖、甘露糖、葡萄糖、木糖和阿拉伯糖组成 ,具有α ,β型糖苷键 ,连接方式有 (1→ 3)、(1→ 4 )、(1→ 2 ) 3种 .PP1分子量通过凝胶过滤法初步测得为 16 .2万左右 .     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that